Carbon Dioxide Capture and Utilization with Isomeric Forms of Bis(amino)-Tagged Zinc Bipyrazolate Metal-Organic Frameworks.

Aiming at extending the tagged zinc bipyrazolate metal-organic frameworks (MOFs) family, the ligand 3,3'-diamino-4,4'-bipyrazole (3,3'-H2 L) has been synthesized in good yield. The reaction with zinc(II) acetate hydrate led to the related MOF Zn(3,3'-L). The compound is isostructural with its mono(amino) analogue Zn(BPZNH2 ) and with Zn(3,5-L), its isomeric parent built with 3,5-diamino-4,4'-bipyrazole. The textural analysis has unveiled its micro-/mesoporous nature, with a BET area of 463 m2 g-1 . Its CO2 adsorption capacity (17.4 wt. % CO2 at pCO2 = 1 bar and T = 298 K) and isosteric heat of adsorption (Qst = 24.8 kJ mol-1 ) are comparable to that of Zn(3,5-L). Both Zn(3,3'-L) and Zn(3,5-L) have been tested as heterogeneous catalysts in the reaction of CO2 with the epoxides epichlorohydrin and epibromohydrin to give the corresponding cyclic carbonates at T = 393 K and pCO2 = 5 bar under solvent- and co-catalyst-free conditions. In general, the conversions recorded are higher than those found for Zn(BPZNH2 ), proving that the insertion of an extra amino tag in the pores is beneficial for the epoxidation catalysis. The best catalytic match has been observed for the Zn(3,5-L)/epichlorohydrin couple, with 64 % conversion and a TOF of 5.3 mmol(carbonate) (mmolZn )-1 h-1 . To gain better insights on the MOF-epoxide interaction, the crystal structure of the [epibromohydrin@Zn(3,3'-L)] adduct has been solved, confirming the existence of Br⋅⋅⋅(H)-N non-bonding interactions. To our knowledge, this study represents the first structural determination of a [epibromohydrin@MOF] adduct.

Single-Stranded DNA as Supramolecular Template for One-Dimensional Palladium(II) Arrays.

Atomic-level control over the position and growth of a single and continuous metal chain is an ambitious goal that often requires complex and costly processes. Herein, we demonstrate that 1Pd-DNA molecules, comprising a continuous single chain of PdII ions, can be prepared by a simple self-assembly reaction between the complex [Pd(Cheld)(CH3 CN)] (1Pd_CH3 CN) (Cheld=chelidamic acid) and single-stranded DNA homopolymers (ss-DNA) containing adenine (A) or 7-deazaadenine (X) bases. The single PdII -base pairs [1Pd(N1-A)] and [1Pd(N1-X)] were synthesized and characterized in solution and solid-state (X-ray diffraction) revealing an arrangement similar to that of natural Watson-Crick base pairs. Subsequently, 1Pd-DNA hybrids were prepared, characterized, and their structures studied by small-angle X-ray scattering (SAXS) and ab-initio calculations. The results indicate that the 1Pd-DNA structures resemble that of double-stranded DNA, with one strand being replaced by a supramolecular stack of continuous PdII complexes.

Zirconium Metal-Organic Frameworks Containing a Biselenophene Linker: Synthesis, Characterization, and Luminescent Properties.

The bicyclic ditopic linker 2,2'-biselenophene-5,5'-dicarboxylic acid (H2SpSp), specifically designed for metal-organic framework (MOF) construction, has been synthesized in good yield and fully characterized. The corresponding zirconium MOF (Zr-MOF) [Zr6O4(OH)4(SpSp)3.8Cl4.4] (1; where missing linkers are replaced by chloride anions as shown by X-ray fluorescence and elemental analysis) is isostructural with its bithiophene and bithiazole analogues. Starting from 1, an extension of the biselenophene-based Zr-MOF family has been successfully achieved, exploiting the structural analogy of the five-membered heterocycles selenophene, thiophene, and thiazole. Thus, three mixed-linker MOFs containing variable amounts of different bis(heterocyclic) dicarboxylic acids have been prepared and fully characterized: the two double-mixed [Zr6O4(OH)4(SpSp)2.6(TpTp)1.3Cl4.2] (2; H2TpTp = 2,2'-bithiophene-5,5'-dicarboxylic acid) and [Zr6O4(OH)4(SpSp)2(TzTz)1.8Cl4.4] (3; H2TzTz = 2,2'-bithiazole-5,5'-dicarboxylic acid) materials, as well as the triple-mixed [Zr6O4(OH)4(SpSp)1.6(TpTp)1.2(TzTz)1.4Cl3.6] (4) compound. The four MOFs are luminescent under UV irradiation, exhibiting emission wavelengths falling in the blue-green visible region, as observed for their constitutive linkers. These materials open new horizons in the preparation of porous luminescent sensors or multicolor emitters for light-emitting diodes.

Comparative Structural Study of Metal-Mediated Base Pairs Formed outside and inside DNA Molecules.

The formation of copper(II)-mediated base pairs involving pyridine-2,6-dicarboxylate derivatives and canonical nucleosides has proven to be a smart approach to introduce copper(II) ions at specific locations of DNA duplexes. However, the structural characteristics of these metalized base pairs have not yet been revealed, and their effect on DNA structures is difficult to assess. Herein, for the first time, we report on the different structural details of copper-mediated base pairs formed by themselves and in DNA duplexes. The individual base pairs [Cu(mcheld)(N3-Cyt)(H2O)]·3H2O (1Cu_Cyt), [Cu(mcheld)(N7-Ade)(H2O)2]·2H2O (1Cu_Ade), [Cu(mcheld)(N7-Gua)(H2O)] (1Cu_Gua), and [Cu(mcheld)(N1-7CAde)(H2O)]·H2O (1Cu_7CAde) were obtained from the reaction of the metal complex [Cu(mcheld)(H2O)2] (1Cu) (mcheld = 4-methoxypyridine-2,6-dicarboxylic acid) with model nucleosides (Cyt = N1-methylcytosine, Ade = N9-ethyladenine, Gua = N9-propylguanine, 7CAde = N9-propyl-7-deazaadenine). The crystal structure of the five complexes was determined by means of single-crystal X-ray diffraction. Furthermore, the formation of the 1Cu_Cyt and 1Cu_Gua base pairs in the middle of DNA duplexes, duplex DNA15 (917 atoms) and DNA10 (649 atoms), respectively, was studied using highly demanding ab initio computational calculations. These theoretical studies aimed to validate, from a structural point of view, whether base pairs of the kind 1Cu_nucleosides can be included in a DNA double helix and how this situation affects the double-helical structure. The results indicate that the 1Cu_Cyt and 1Cu_Gua base pairs can be formed in a DNA molecule without significant structural constraints. In addition, the double-helix DNA structure remains virtually unchanged when it contains these Cu(II)-mediated base pairs.

Cobalt(II) Bipyrazolate Metal-Organic Frameworks as Heterogeneous Catalysts in Cumene Aerobic Oxidation: A Tag-Dependent Selectivity.

Three metal-organic frameworks with the general formula Co(BPZX) (BPZX2- = 3-X-4,4'-bipyrazolate, X = H, NH2, NO2) constructed with ligands having different functional groups on the same skeleton have been employed as heterogeneous catalysts for aerobic liquid-phase oxidation of cumene with O2 as oxidant. O2 adsorption isotherms collected at pO2 = 1 atm and T = 195 and 273 K have cast light on the relative affinity of these catalysts for dioxygen. The highest gas uptake at 195 K is found for Co(BPZ) (3.2 mmol/g (10.1 wt % O2)), in line with its highest BET specific surface area (926 m2/g) in comparison with those of Co(BPZNH2) (317 m2/g) and Co(BPZNO2) (645 m2/g). The O2 isosteric heat of adsorption (Qst) trend follows the order Co(BPZ) > Co(BPZNH2) > Co(BPZNO2). Interestingly, the selectivity in the cumene oxidation products was found to be dependent on the tag present in the catalyst linker: while cumene hydroperoxide (CHP) is the main product obtained with Co(BPZ) (84% selectivity to CHP after 7 h, pO2 = 4 bar, and T = 363 K), further oxidation to 2-phenyl-2-propanol (PP) is observed in the presence of Co(BPZNH2) as the catalyst (69% selectivity to PP under the same experimental conditions).

Nitro-functionalized Bis(pyrazolate) Metal-Organic Frameworks as Carbon Dioxide Capture Materials under Ambient Conditions.

The metal-organic frameworks (MOFs) M(BPZNO2 ) (M=Co, Cu, Zn; H2 BPZNO2 =3-nitro-4,4'-bipyrazole) were prepared through solvothermal routes and were fully investigated in the solid state. They showed good thermal stability both under a N2 atmosphere and in air, with decomposition temperatures peaking up to 663 K for Zn(BPZNO2 ). Their crystal structure is characterized by 3D networks with square (M=Co, Zn) or rhombic (M=Cu) channels decorated by polar NO2 groups. As revealed by N2 adsorption at 77 K, they are micro-mesoporous materials with BET specific surface areas ranging from 400 to 900 m2 g-1 . Remarkably, under the mild conditions of 298 K and 1.2 bar, Zn(BPZNO2 ) adsorbs 21.8 wt % CO2 (4.95 mmol g-1 ). It shows a Henry CO2 /N2 selectivity of 15 and an ideal adsorbed solution theory (IAST) selectivity of 12 at p=1 bar. As a CO2 adsorbent, this compound is the best-performing MOF to date among those bearing a nitro group as a unique chemical tag. High-resolution powder X-ray diffraction at 298 K and different CO2 loadings revealed, for the first time in a NO2 -functionalized MOF, the insurgence of primary host-guest interactions involving the C(3)-NO2 moiety of the framework and the oxygen atoms of carbon dioxide, as confirmed by Grand Canonical Monte Carlo simulations. This interaction mode is markedly different from that observed in NH2 -functionalized MOFs, for which the carbon atom of CO2 is involved.

Ultrafast Molecular Rotors and Their CO2 Tuning in MOFs with Rod-Like Ligands.

A metal organic framework (MOF) engineered to contain in its scaffold rod-like struts featuring ultrafast molecular rotors showed extremely rapid 180 ° flip reorientation with rotational rates of 1011  Hz at 150 K. Crystal-pore accessibility of the MOF allowed the CO2 molecules to enter the cavities and control the rotor spinning speed down to 105  Hz at 150 K. Rotor dynamics, as modulated by CO2 loading/unloading in the porous crystals, was described by proton T1 and 2 H NMR spectroscopy. This strategy enabled the regulation of rotary motion by the diffusion of the gas within the channels and the determination of the energetics of rotary dynamics in the presence of CO2 .

Metal Azolate/Carboxylate Frameworks as Catalysts in Oxidative and C-C Coupling Reactions.

The five metal azolate/carboxylate (MAC) compounds [Cd(dmpzc)(DMF)(H2O)] (Cd-dmpzc), [Pd(H2dmpzc)2Cl2] (Pd-dmpzc), [Cu(Hdmpzc)2] (Cu-dmpzc), [Zn4O(dmpzc)3]·Solv (Zn-dmpzc·S), and [Co4O(dmpzc)3]·Solv (Co-dmpzc·S) were isolated by coupling 3,5-dimethyl-1H-pyrazol-4-carboxylic acid (H2dmpzc) to cadmium(II), palladium(II), copper(II), zinc(II), and cobalt(II) salts. While Cd-dmpzc and Pd-dmpzc had never been prepared in the past, for Cu-dmpzc, Zn-dmpzc·S, and Co-dmpzc·S we optimized alternative synthetic paths that, in the case of the copper(II) and cobalt(II) derivatives, are faster and grant higher yields than the previously reported ones. The crystal structure details were determined ab initio (Cd-dmpzc and Pd-dmpzc) or refined (Cu-dmpzc, Zn-dmpzc·S, and Co-dmpzc·S) by means of powder X-ray diffraction (PXRD). While Cd-dmpzc is a nonporous 3D MAC framework, Pd-dmpzc shows a 3D hybrid coordination/hydrogen-bonded network, in which Pd(H2dmpzc)2Cl2 monomers are present. The thermal behavior of the five MAC compounds was investigated by coupling thermal analysis to variable-temperature PXRD. Their catalytic activity was assessed in oxidative and C-C coupling reactions, with the copper(II) and cadmium(II) derivatives being the first nonporous MAC frameworks to be tested as catalysts. Cu-dmpzc is the most active catalyst in the partial oxidation of cyclohexane by tert-butyl hydroperoxide in acetonitrile (yields up to 12% after 9 h) and is remarkably active in the solvent-free microwave-assisted oxidation of 1-phenylethanol to acetophenone (yields up to 99% at 120 °C in only 0.5 h). On the other hand, activated Zn-dmpzc·S (Zn-dmpzc) is the most active catalyst in the Henry C-C coupling reaction of aromatic aldehydes with nitroethane, showing appreciable diastereoselectivity toward the syn-nitroalkanol isomer (syn:anti selectivity up to 79:21).

CO2 Adsorption in a Robust Iron(III) Pyrazolate-Based MOF: Molecular-Level Details and Frameworks Dynamics From Powder X-ray Diffraction Adsorption Isotherms.

Understanding adsorption processes at the molecular level, with multi-technique approaches, is nowadays at the frontier of porous materials research. In this work it is shown that with a proper data treatment, in situ high-resolution powder X-ray diffraction (HR-PXRD) at variable temperature and gas pressure can reveal atomic details of the accommodation sites, the framework dynamics as well as thermodynamic information (isosteric heat of adsorption) of the CO2 adsorption process in the robust iron(III) pyrazolate-based MOF Fe2(BDP)3 [H2BDP = 1,4-bis(1H-pyrazol-4-yl)benzene]. Highly reliable "HR-PXRD adsorption isotherms" can be constructed from occupancy values of CO2 molecules. The "HR-PXRD adsorption isotherms" accurately match the results of conventional static and dynamic gas sorption experiments and Monte Carlo simulations. These results are indicative of the impact of the molecular-level behavior on the bulk properties of the system under study and of the potential of the presented multi-technique approach to understand adsorption processes in metal-organic frameworks.

Rollover cyclometalation with 2-(2'-pyridyl)quinoline.

Rollover cyclometalation of 2-(2'-pyridyl)quinoline, L, allowed the synthesis of the family of complexes [Pt(L-H)(X)(L')] and [Pt(L*)(X)(L')][BF4] (X = Me, Cl; L' = neutral ligand), the former being the first examples of Pt(II) rollover complexes derived from the ligand L. The ligand L* is a C,N cyclometalated, N-protonated isomer of L, and can also be described as an abnormal-remote pyridylene. The corresponding [Pt(L-H)(Me)(L')]/[Pt(L*)(Me)(L')](+) complexes constitute an uncommon Brønsted-Lowry acid-base conjugated couple. The species obtained were investigated in depth through NMR and UV-vis spectroscopy, cyclic voltammetry, and density functional theory (DFT) methods to correlate different chemico-physical properties with the nature of the cyclometalated ligand (e.g., L vs bipy or L* vs L) and of the neutral ligand (DMSO, CO, PPh3). The crystal structures of [Pt(L-H)(Me)(PPh3)], [Pt(L-H)(Me)(CO)] and [Pt(L*)(Me)(CO)][BF4] were determined by X-ray powder diffraction methods, the latter being the first structure of a Pt(II)-based, protonated, rollover complex to be unraveled. The isomerization of [Pt(L*)(Me)(PPh3)](+) in solution proceeds through a retro-rollover process to give the corresponding adduct [Pt(L)(Me)(PPh3)](+), where L acts as a classical N,N chelating ligand. Notably, the retro-rollover reaction is the first process, among the plethora of Pt-C bond protonolysis reactions reported in the literature, where a Pt-C(heteroaryl) bond is cleaved rather than a Pt-C(alkyl) one.

Synthesis of a new sulfonated-hexachlorobiphenyl standard for environmental analysis, ecotoxicological, and toxicological studies.

Sulfonated-polychlorinated biphenyls (sulfonated-PCBs) are a newly discovered class of PCB metabolites. They were observed for the first time in polar bear serum and lately, in soil, together with hydroxy-sulfonated-PCBs. Their presence is ubiquitous in soils, and their estimated physical chemical properties show high mobility in water, compared to the parent compounds. However, no single pure standards exist so far and therefore their quantification in the environmental matrices is not accurate. Additionally, pure standards are needed to experimentally determine their physical chemical properties, as well as the ecotoxicological and toxicological characteristics. In the present work, the challenging goal of preparing a polychlorinated biphenyl monosulfonic acid was achieved exploring different synthetic approaches, along which the selection of the starting material resulted in a crucial point. Using PCB-153 (2,2'-4,4'-5,5'-hexachloro-1,1'-biphenyl) the synthesis afforded, as the major species, a side compound. On the contrary, the use of PCB-155 (2,2'-4,4'-6,6'-hexachloro-1,1'-biphenyl), a symmetric hexachlorobiphenyl derivative showing chlorine atoms at all the ortho positions, gave the target sulfonated-PCB compound. In this case, sulfonation was successfully carried out through a two-step procedure, involving chlorosulfonylation and the subsequent hydrolysis of the chlorosulfonyl intermediate.

Mercury Clathration-Driven Phase Transition in a Luminescent Bipyrazolate Metal-Organic Framework: A Multitechnique Investigation.

Mercury is one of the most toxic heavy metals. By virtue of its triple bond, the novel ligand 1,2-bis(1H-pyrazol-4-yl)ethyne (H2BPE) was expressly designed and synthesized to devise metal-organic frameworks (MOFs) exhibiting high chemical affinity for mercury. Two MOFs, Zn(BPE) and Zn(BPE)·nDMF [interpenetrated i-Zn and noninterpenetrated ni-Zn·S, respectively; DMF = dimethylformamide], were isolated as microcrystalline powders. While i-Zn is stable in water for at least 15 days, its suspension in HgCl2 aqueous solutions prompts its conversion into HgCl2@ni-Zn. A multitechnique approach allowed us to shed light onto the observed HgCl2-triggered i-Zn-to-HgCl2@ni-Zn transformation at the molecular level. Density functional theory calculations on model systems suggested that HgCl2 interacts via the mercury atom with the carbon-carbon triple bond exclusively in ni-Zn. Powder X-ray diffraction enabled us to quantify the extent of the i-Zn-to-HgCl2@ni-Zn transition in 100-5000 ppm HgCl2 (aq) solutions, while X-ray fluorescence and inductively coupled plasma-mass spectrometry allowed us to demonstrate that HgCl2 is quantitatively sequestered from the aqueous phase. Irradiating at 365 nm, an intense fluorescence is observed at 470 nm for ni-Zn·S, which is partially quenched for i-Zn. This spectral benchmark was exploited to monitor in real time the i-Zn-to-HgCl2@ni-Zn conversion kinetics at different HgCl2 (aq) concentrations. A sizeable fluorescence increase was observed, within a 1 h time lapse, even at a concentration of 5 ppb. Overall, this comprehensive investigation unraveled an intriguing molecular mechanism, featuring the disaggregation of a water-stable MOF in the presence of HgCl2 and the self-assembly of a different crystalline phase around the pollutant, which is sequestered and simultaneously quantified by means of a luminescence change. Such a case study might open the way to new-conception strategies to achieve real-time sensing of mercury-containing pollutants in wastewaters and, eventually, pursue their straightforward and cost-effective purification.

Tuning the adsorption properties of isoreticular pyrazolate-based metal-organic frameworks through ligand modification.

Two isoreticular series of pyrazolate-based 3D open metal-organic frameworks, MBDP_X, adopting the NiBDP and ZnBDP structure types [H(2)BDP = 1,4-bis(1H-pyrazol-4-yl)benzene], were synthesized with the new tagged organic linkers H(2)BDP_X (X = -NO(2), -NH(2), -OH). All of the MBDP_X materials have been characterized through a combination of techniques. IR spectroscopy proved the effective presence of tags, while X-ray powder diffraction (XRPD) witnessed their isoreticular nature. Simultaneous TG/DSC analyses (STA) demonstrated their remarkable thermal stability, while variable-temperature XRPD experiments highlighted their high degree of flexibility related to guest-induced fit processes of the solvent molecules included in the channels. A structural isomer of the parent NiBDP was obtained with a sulfonate tagged ligand, H(2)BDP_SO(3)H. Structure solution from powder diffraction data collected at three different temperatures (room temperature, 90, and 250 °C) allowed the determination of its structure and the comprehension of its solvent-related flexible behavior. Finally, the potential application of the tagged MOFs in selective adsorption processes for gas separation and purification purposes was investigated by conventional single component adsorption isotherms, as well as by advanced experiments of pulse gas chromatography and breakthrough curve measurements. Noteworthy, the results show that functionalization does not improve the adsorption selectivity (partition coefficients) for the resolution of gas mixtures characterized by similar high quadrupole moments (e.g., CO(2)/C(2)H(2)); however, the resolution of gas mixtures containing molecules with highly differentiated polarities (i.e., N(2)/CO(2) or CH(4)/CO(2)) is highly improved.

Novel coordination frameworks incorporating the 4,4'-bipyrazolyl ditopic ligand.

The reaction of the rigid spacer 4,4'-bipyrazole (H(2)BPZ) with late transition metals, either following conventional routes or under solvothermal conditions, afforded the coordination polymers [M(BPZ)]·Solv (M = Zn, 1; Co, 2; Cd, 3; Hg, 4; Cu, 5; Ni, 6; Pd, 7; Solv = DMF, 3; MeCN, 5 and 6; H(2)O, 7), [Cu(H(2)BPZ)(2)(NO(3))(2)] (8), and [Cd(H(2)BPZ)(CH(3)COO)(2)] (9). State-of-the-art laboratory powder diffraction methods allowed to disclose the isomorphous character of 1 and 2, as well as of 5 and 6, which feature 3D porous networks containing 1D channels of square and rhombic shape, respectively. 3, crystallizing in the relatively rare P6(1)22 space group, consists of homochiral helices of octahedral Cd(II) ions, packing in bundles mutually linked by "radial", nonplanar BPZ ligands. Finally, the dense species 8 and 9 contain parallel 2D layers of square and rectangular meshes, respectively. Thermogravimetric analyses witnessed the relevant thermal robustness of all the [M(BPZ)] materials [except the mercury(II) derivative], which are stable in air at least up to 300 °C, with the zinc(II) derivative decomposing only around 450 °C. Variable-temperature powder diffraction experiments highlighted the permanent porosity of 1-3, 5, and 6, retained along consecutive temperature cycles in all cases but 3. When probed with N(2) at 77 K, 1-3 and 5-7 showed Brunauer-Emmett-Teller and Langmuir specific surface areas in the ranges 314(2)-993(11) and 509(16)-1105(1) m(2)/g, respectively.

Antibacterial action of 4,4'-bipyrazolyl-based silver(I) coordination polymers embedded in PE disks.

Coupling the rigid spacer 4,4'-bipyrazole (H(2)BPZ), in its anionic or neutral form, to different silver(I) salts allowed isolation of the novel coordination polymers [Ag(2)(BPZ)] (1) and [Ag(H(2)BPZ)(X)] (X = NO(3), 2; ClO(4), 3; BF(4), 4; PF(6), 5; CH(3)SO(3), 6; CF(3)SO(3), 7), which were fully characterized by infrared and emission spectroscopies, thermal analysis, and X-ray powder diffraction. The crystal structure of 1 consists of 2-D layers containing 1-D chains of Ag(I) ions bridged by exo-tetradentate bipyrazolato moieties. The crystal structures of the [Ag(H(2)BPZ)(X)] species 2-7 feature 1-D chains of [Ag(H(2)BPZ)] stoichiometry, along which the metal centers are bridged by exo-bidentate bipyrazolyl spacers. Contacts among adjacent chains are mediated by the counterions through nonbonding interactions involving the Ag(I) ions and the pyrazolyl N-H groups. Thermogravimetric analyses disclosed the good thermal stability of these materials, decomposing in the range 200-300 °C. Under UV irradiation at room temperature, all the species showed a yellow-green emission centered in the range 520-522 nm. When embedded into polyethylene disks, 1, 2, and 4-7 demonstrated their activity as topical antibacterial agents against suspensions of E. coli, P. aeruginosa, and S. aureus: complete reduction of the three bacterial strains was achieved in 24 h, reduction of S. aureus reaching ca. 90% in only 2 h. Biocidal action was expressed also by contact susceptibility tests.

Impact of Pore Flexibility in Imine-Linked Covalent Organic Frameworks on Benzene and Cyclohexane Adsorption.

This work focuses on the impact of covalent organic frameworks' (COFs) pore flexibility in the adsorption and separation of benzene and cyclohexane. With this aim, we have selected the imine-linked 3D COFs COF-300 and LZU-111 as examples of flexible and rigid frameworks, respectively. Optimized syntheses at room temperature or in solvothermal conditions enabled us to selectively isolate the narrow-pore form of COF-300 (COF-300-rt) or a mixture of the narrow-pore and a larger-pore form (COF-300-st), respectively, with different textural properties (BET specific surface area = 39 or 1270 m2/g, respectively, from N2 adsorption at 77 K). In the case of LZU-111, only the room temperature route was successful, leading to the known microporous framework. COF-300-rt, COF-300-st, and LZU-111 were studied for benzene and cyclohexane adsorption and separation in static and dynamic conditions. At 298 K and 1 bar, these COFs adsorb more benzene (251, 221, and 214 cm3/g STP, respectively) than cyclohexane (175, 133, and 164 cm3/g STP, respectively). Moreover, the benzene and cyclohexane isotherms of COF-300-rt and COF-300-st are characterized by steps, as expected with a flexible material. Indeed, in situ powder X-ray diffraction experiments on benzene- and cyclohexane-impregnated batches enabled us to trap, for the first time, a sequence of forms of COF-300 with different pore aperture, rationalizing the stepped hysteretic isotherms. Finally, benzene/cyclohexane separation was evaluated using a benzene/cyclohexane 50:50 v/v flow at different temperatures (T = 298, 323, and 348 K): LZU-111 does not selectively retain any of the two components, while COF-300 exhibits stronger benzene-COF interactions also in dynamic conditions.

The Effects of Park Based Interventions on Health: The Italian Project "Moving Parks".

Obesity and physical inactivity are global health problems responsible for the risk increment of noncommunicable diseases. To overcome these problems, interventions aimed at increasing physical activity (PA) are necessary. Green space can have a positive influence on promoting PA, so, the aim of the present study was to assess the effectiveness of the project "The moving parks project", which provides for the administration of PA to citizens within Bologna's parks (Italy). An ad hoc questionnaire was administered before and after three months of outdoor PA. A total of 329 adult subjects participated in the survey. At follow-up, all psychosocial parameters showed an improvement, with a reduction in the state of tension, sadness and fatigue, and an improvement in the state of energy, serenity, and vitality. The impact of the interventions carried out in the "Moving Parks project" was positive and appears to be a good strategy for improving health outcomes.

Zirconium Metal-Organic Polyhedra with Dual Behavior for Organophosphate Poisoning Treatment.

Organophosphate nerve agents and pesticides are extremely toxic compounds because they result in acetylcholinesterase (AChE) inhibition and concomitant nerve system damage. Herein, we report the synthesis, structural characterization, and proof-of-concept utility of zirconium metal-organic polyhedra (Zr-MOPs) for organophosphate poisoning treatment. The results show the formation of robust tetrahedral cages [((n-butylCpZr)3(OH)3O)4L6]Cl6 (Zr-MOP-1; L = benzene-1,4-dicarboxylate, n-butylCp = n-butylcyclopentadienyl, Zr-MOP-10, and L = 4,4'-biphenyldicarboxylate) decorated with lipophilic alkyl residues and possessing accessible cavities of ∼9.8 and ∼10.7 Šinner diameters, respectively. These systems are able to both capture the organophosphate model compound diisopropylfluorophosphate (DIFP) and host and release the AChE reactivator drug pralidoxime (2-PAM). The resulting 2-PAM@Zr-MOP-1(0) host-guest assemblies feature a sustained delivery of 2-PAM under simulated biological conditions, with a concomitant reactivation of DIFP-inhibited AChE. Finally, 2-PAM@Zr-MOP systems have been incorporated into biocompatible phosphatidylcholine liposomes with the resulting assemblies being non-neurotoxic, as proven using neuroblastoma cell viability assays.

Effect of a Park-Based Physical Activity Intervention on Psychological Wellbeing at the Time of COVID-19.

Practicing regular physical activity in green spaces has been invocated as a promising strategy for improving wellbeing in urban settings. The aim of the study was to assess the effect of a structured park-based physical activity intervention, the "Moving Parks" project, on citizens' wellbeing at the time of COVID-19. The intervention was carried out in six public parks in Bologna (Italy) and administered by qualified instructors (from May 2021 to September 2021). The Psychological General Well Being Index short form questionnaire was administered before and after the three months of outdoor activities. A total of 328 participants completed the questionnaire at the beginning and at the end of the project. In September 2021, all psychosocial domains of the questionnaire (anxiety, depressed mood, self-control, positive well-being, vitality energy, and vitality-tiredness) significantly improved in the female sample (p value < 0.01) and only the last two in the male sample (p value < 0.05). The "Moving Parks" project seems to be able to improve citizens' psychological wellbeing, particularly in women.

Capture of nerve agents and mustard gas analogues by hydrophobic robust MOF-5 type metal-organic frameworks.

In this communication, a series of observations and data analyses coherently confirms the suitability of the novel metal-organic framework (MOF) [Zn(4)(µ(4)-O)(µ(4)-4-carboxy-3,5-dimethyl-4-carboxy-pyrazolato)(3)] (1) in the capture of harmful volatile organic compounds (VOCs). It is worthy of attention that 1, whose crystal structure resembles that of MOF-5, exhibits remarkable thermal, mechanical, and chemical stability, as required if practical applications are sought. In addition, it selectively captures harmful VOCs (including models of Sarin and mustard gas, which are chemical warfare agents), even in competition with ambient moisture (i.e., under conditions mimicking operative ones). The results can be rationalized on the basis of Henry constant and adsorption heat values for the different essayed adsorbates as well as H(2)O/VOC partition coefficients as obtained from variable-temperature reverse gas chromatography experiments. To further strengthen the importance of 1, its performance in the capture of harmful VOCs has been compared with those of well-known materials, namely, a MOF with coordinatively unsaturated metal sites, [Cu(3)(btc)(2)] and the molecular sieve active carbon Carboxen. The results of this comparison show that coordinatively unsaturated metal sites (preferential guest-binding sites) are ineffective for the capture of VOCs in the presence of ambient moisture. Consequently, we propose that the driving force of the VOC-MOF recognition process is mainly dictated by pore size and surface hydrophobicity.